Field of the Invention
This invention relates to an electric switch and in particular to a sealed double pole switch which requires the actuator to be manually lifted back to a reset position.
Description of Related Art
There are many types of electrical applications requiring different features in a switch that must quickly change from one state to another, and often the switches that are available fail to meet a particular important application criteria. There are snap-acting switches, double pole switches, toggle switches, momentary pushbutton switches, switches that are sealed from the application environment, normally xe2x80x9copenxe2x80x9d switches and normally xe2x80x9cclosedxe2x80x9d switches.
An application of an electrical switch where human safety is top priority created the need for an improved switch that is miniature, double pole, fixed position, internally sealed, difficult to reset unless a tool is used, has minimal travel of activate button, very reliable and tamperproof.
Examples of sealed switches and snap-action switches include U.S. Pat. No. 2,748,229 entitled xe2x80x9cWater Tight Switchxe2x80x9d and issued May 29, 1956 to E. H. Block discloses a cam operated water tight switch operated by depressing a plunger. In order to insure a water tight connection between casing and wall, a ring of solder is heat sealed in groove in casing. The switch comprises the plunger having a pushbutton slidably mounted in bore. An O-ring gasket is mounted in a groove of the plunger for preventing ingress of water to the interior of switch casing. The plunger has a threaded extension and a tubular member and a hollow cylindrical plug. A pair of micro switches having operating pins are operated by spring arms 48 extending from member having a cam surface when the plunger is moved inwardly. A spring returns the tubular member to the initial position and springs are released by cam surfaces.
U.S. Pat. No. 2,519,297 entitled xe2x80x9cCircuit Breakerxe2x80x9d and issued Aug. 15, 1950 to Clare A. Stump, Jr. et al. discloses a circuit breaker of the snap-acting type. The circuit breaker comprises a pair of resilient switch members having movable contact members secured to the ends thereof. The movable contacts on the switch member are adapted to cooperate with stationary contacts on the inner ends of conductors which extend in opposite directions to the exterior of the casing where they form terminal connectors. An operating rod is manually pushed or pulled to close or open the circuit breaker, and a trip device automatically opens the circuit breaker in response to overload currents. In order to reset and relatch the trip device and the actuating plunger, the pushbutton is pulled out to its extreme outward position.
U.S. Pat. No. 2,750,463 entitled xe2x80x9cElectric Switches of the Snap-Action Typexe2x80x9d and issued Jun. 12, 1956 to J. O. Roeser discloses an electric snap-action switch having a double-pole double-throw action, the double-throw being simultaneous. The switch comprises two sections arranged superimposed and connected to each other and to a mounting plate. Each section comprises terminal arms having stationary contacts on interior end portions, a spring plate having contacts on each end for contacting contacts, and a plunger having a stem attached to an actuator button. The plunger is provided with a socket into which partially extends an actuating stem in an upper section having a lower end attached to intermediate plunger which in turn is connected to the actuating stem which moves the spring plate in the lower switch section. The movement of the contacts provides a xe2x80x9cmake before breakxe2x80x9d switch.
The present invention comprises a novel combination and arrangement of parts to be hereinafter described and claimed.
Accordingly, it is therefore an object of this invention to provide an electric switch that is double poled, and requires an actuator to be manually lifted back to an unactuated or xe2x80x9cbreakxe2x80x9d position with a tool.
It is another object of this invention to provide a doubled pole switch that is internally sealed including use of an O-ring for sealing the actuator at the top of the switch assembly.
It is a further object of this invention to provide an actuator that is depressed to a xe2x80x9cmakexe2x80x9d position and manually lifted back to a xe2x80x9cbreakxe2x80x9d position.
It is another object of this invention to provide four terminals in a base along with an actuator and blade/contact assemblies wherein wires are attached to the terminals and routed to exit the base from the same bottom channel.
These and other objects are accomplished by a double pole switch requiring use of a tool for resetting the switch comprising a housing having a plurality of pedestals for supporting a first pair of terminals positioned opposite each other and a second pair of terminals positioned opposite each other and spaced apart from the first pair of terminals, an actuator positioned in an opening of the housing between the first pair of terminals and the second pair of terminals, the actuator having at least two pair of notches spaced apart from each other, a first blade having contacts at opposite ends and a portion of the first blade in contact with an upper pair of the spaced apart notches of the actuator, the actuator passing through the first blade wherein the first blade is positioned to make electrical contact with the first pair of terminals when the switch is in a xe2x80x9cmakexe2x80x9d position, and a second blade having contacts at opposite ends and a portion of the second blade in contact with a lower pair of the spaced apart notches of the actuator, the actuator passing through the second blade wherein the second blade is positioned to make electrical contact with the second pair of terminals when the switch is in a xe2x80x9cmakexe2x80x9d position. The housing comprises a base having a channel for wires to pass through and an outer shell for enclosing the base and receiving an upper portion of the actuator which extends above the shell when the switch is in a xe2x80x9cbreakxe2x80x9d position. The first pair of terminals are U-shaped for fitting around a pair of the opposite pedestals formed in the base. Each of the terminals of the first pair and the second pair comprises a wire electrically connected thereto and extending outside of the switch. An upper portion of the actuator comprises a groove around the circumference of the actuator for receiving an O-ring thereby sealing the upper portion of the switch when the base is inserted within an outer shell. The switch comprises means for sealing an opening between a lower portion of the base and the outer shell. The switch comprises heat/shrink material around the base and wires passing through the base. The top portion of the actuator comprises a slot for insertion of the tool for moving the actuator from the xe2x80x9cmakexe2x80x9d position to a xe2x80x9cbreakxe2x80x9d position. The top portion of an outer shell of the switch comprises an opening to enable insertion of the tool into the slot of the actuator. The portion of the first blade in contact with an upper pair of spaced apart notches of the actuator comprises a pair of tongues. The portion of the second blade in contact with a lower pair of the spaced apart notches of the actuator comprises a pair of tongues. The base comprises an open channel for receiving each wire from the terminals protruding a predetermined distance from the bottom of the base, the open channel further comprises a lip around the end of the open channel. The switch comprises heat shrink material for sealing off any openings at the lip of the channel.
The object are further accomplished by a sealed, manual reset, double pole switch comprising a housing having a base portion and an outer shell portion, a pair of spaced apart parallel blades positioned within the base having contacts on opposite ends and an actuator positioned through the parallel blades and perpendicular thereto, at least four terminals mounted on pedestals within the base portion, the terminals making electrical contact with the blade contacts when the switch is in a xe2x80x9cmakexe2x80x9d position and the actuator extends above a top portion of the outer shell, the actuator comprises a groove around the circumference of the actuator for receiving an O-ring thereby sealing the upper portion of the switch, the switch comprises means for sealing an opening between a lower portion of the base and the outer shell, the base comprises a channel for wires to pass through and connect to the terminals and heat shrink material applied around an end of the channel and around the wires, and a slot provided in the top portion of the outer shell and the actuator for insertion of a tool to move the actuator from the xe2x80x9cmakexe2x80x9d position to a xe2x80x9cbreakxe2x80x9d position to accomplish a reset of the switch.
Additional objects, features and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of the preferred embodiment exemplifying the best mode of carrying out the invention as presently perceived.